5/4/2010 - Fuel filtration

I may have written about some of this stuff before but I finalized the installation today so here's a little reprise:

If you've read one of my earliest entries, telling about our trip down the Washington and Oregon coasts, you know about the hassles we had with fuel filters. At the time I wrote the whole thing off to crud in the fuel tank being stirred up. Since that time I have read quite a bit about fuel filtration. One thing that stands out is that you can find at least one "expert" to back up whatever filtration strategy you choose. Of course, that's the story of nearly everything associated with sailing and cruising.

One of the jobs I did a few months ago was to cut an access hole into my fuel tank so that it could be opened up and cleaned by hand occasionally.

What I found when I dug in and started cleaning the tank was that it wasn't really that dirty. Sure there was some crud down at the very bottom but it was pretty well stuck in place. This led me to rethink what our problem was when coming down the coast. After doing some more reading to find an "expert" to back up the theory that I chose to believe, I decided that we probably were WAY over-filtering the fuel. I had switched filter elements in our primary filter from 30 microns to 2 microns. This is the same size filter that is installed on my engine as the final filter. I figured that, rather than rely on my engine-mounted filter (which is pretty small and somewhat of a hassle to change) I would just filter out all that stuff at the beginning of the line and probably never have to change the engine-mounted filter as a result. And, the theory sort of worked.

What I hadn't thought about was how often the 2 micron primary filter was going to plug up. On our trip down, I found out. It's a lot.

So, my next move was to install a regular Racor filter with a 30 micron element as my primary filter. If I'd had that on the way down the coast we may have never had to swap filters en route. But, that's not all. In the off chance that we do have to change filters while underway, I'd like to be able to do it on my schedule. Don't want the filter plugging up and stopping the engine during some critical operation. So, I borrowed a trick from the big guys and installed twin filters with switchover valves between them so that, in the event of a plug-up, I can simply switch 2 valves and I'm once again operating with a clean filter. Now, I can change elements when it's convenient.

And that was where things stood until today. The boat originally came to us equipped with a Racor canister filter unit. It's kind of a nice unit but the elements are ridiculously expensive. I was going to shitcan the unit and just use the 30 micron filters and the engine-mounted filter. However, after finding out what the canister units cost, I decided it would be foolish not to find a use for it. So, I reinstalled it and installed a 2 micron element. This then will serve as the polishing filter, easing the load on the engine-mounted unit.

I managed to get it all back together without any leaks and without any spills. I'd like to say that my trusty little Westerbeke diesel, which is advertised as "self-bleeding" fired right up. However, because I didn't pre-fill the new filter with clean fuel, there is a LOT of air to bleed off. I have always been amazed in the past at the level which the engine will self-bleed so I decided to put it to the big test while I'm still connected to shore power and therefore, unlimited battery-charging capability. By the time I decided to give things a rest, the new filter was full of fuel but the engine hadn't fired yet. I'm letting it sit to see if the air will work its way up to the self-bleeding unit (wherever that is) and will then miraculously start next time I try. Hey, it's happened before!

I was able to do all of this plumbing through the engine room door at the base of the companionway ladder. Lulu had been planning to do some sewing but was afraid she'd be in the way. But we decided that we really needed to learn to be able to work on 2 projects at the same time because we're going to have to in the near future. The good news is, we both got our jobs done, no one got hurt, no one got mad, and we were never really in each other's way.

Hey, take a look at this view of the engine room. It really is a room and the size is unprecedented for almost any sailboat, much less a 28 foot sailboat.

You're looking aft through the door behind the companionway ladder. The engine room is also accessible from above through a hatch in the cockpit floor. Behind the engine is a huge Edson diaphragm pump mounted on a piece of plywood. It's got a 2-1/2' handle and will pump something like a gallon per stroke. We used it to great advantage when we got to our old boat late one Friday night and found the floorboards floating. The boat was not terribly raintight, it had rained a lot since our last visit and, at the time, it didn't have an electric bilge pump. We've learned a lot since then. At any rate, the point is that this is one herkin' big manual pump. Behind the pump base you're looking into the lazerette.

To starboard of the engine is a shelf which houses our 2 group 27 starting batteries, our Honda 2000 generator (sporting a Lulu-made custom canvas cover), as well as a bunch of miscellaneous pieces of lumber. A Webasto diesel forced-air heater and a Whale gusher bilge pump are located above the Honda. Most boats seem to be built with the absolute smallest space for the engine that they can get away with. This is okay if, by removing some panels you can expose the beast. But I've read about boats where you had to lay down on the quarter berth, and then reach (one-armed) through an access hatch to change oil filters, etc. Those boats undoubtedly have more stowage space, but I'll take my proper engine "room" anytime.

PS: a future blog will talk about the sewing project that Lulu is working on. But I want to wait until it's done so you can get the big picture.